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Need help to convert Lambert Conformal Conic Grids to longlat (WGS84)
Added by Arindan Mandal about 3 years ago
Hi,
I am working with HAR (.nc) datasets (https://www.klima.tu-berlin.de/index.php?show=daten_har). They are in Lambert Conformal Conic Grids, the map projection used by the WRF model.
But to work with them in R, I need to convert them into latlong (wgs84) as my other datasets are already in latlong. I want them as latitude longitude, so that I can play with them, e.g. crop, mask for several polygons, etc (in R).
I was using "cdo setgridtype,curvilinear" operator to convert them in latlon, but finally it shows same grid/axis, no latitude longitude.
I have attached a sample of data of the same.
Would be happy if one can guide me a little to overcome this. Also attached the figures before and after conversion (plotted in R).
hi Arindan!
I could interpolate you HAR file to a global lonlat-grid with
cdo -P 8 remapbil,global_0.1 HAR_v2_d10km_m_2d_prcp_2004.nc out.nc
for shrinking the grid an additional
sellonlatbox like
-sellonlatbox,61,111,23,48
Finally
cdo -L -P 8 -sellonlatbox,61,111,23,48 -remapbil,global_0.1 HAR_v2_d10km_m_2d_prcp_2004.nc t.nc
plotted with psy-view
Mr. Ralf Mueller,
This solves my requirement.
Thank you very much for the nice stuff.
Hello,
do you also know how to do this conersion in python?
Thank you.
Hi Fadel,
for python-cdo:
from cdo import *
cdo = Cdo()
cdo.sellonlatbox('61,111,23,48', input='-remapbil,global_0.1 HAR_v2_d10km_m_2d_prcp_2004.nc', output='t.nc', options = '-P 8')
-Karin
